OBJECTIVE: To evaluate signs of haemolysis in babies of Rh-D negative mothers who underwent prophylaxis with anti-D immunoglobulin during pregnancy. DESIGN: The following were evaluated in all babies of Rh-D negative mothers born within a three month period in our department: haemoglobin level, packed cell volume, mean corpuscular volume, reticulocytes, bilirubin level, and direct Coombs' test (direct anti-globulin test). The babies were divided into two groups according to number of doses of anti-D immunoglobulin received by the mother (one or two), and then further divided by their Rh status (negative or positive). Findings were also compared with a control group of babies of O-Rh positive mothers. RESULTS: The study group consisted of 101 babies and the control group of 37 babies. No statistically significant differences were found for any of the haematological variables between the babies of mothers who received one or two doses of anti-D immunoglobulin, or between the Rh negative babies (n = 35), and the controls. Although 20% of the Rh positive babies born to mothers receiving two doses of anti-D immunoglobulin had a positive result in the direct Coombs' test compared with only 2.4% of the babies of mothers treated with only one dose, no signs of haemolysis were documented in the babies with a positive Coombs test. CONCLUSION: The prevention of Rh isoimmunisation with anti-D immunoglobulin (one or two doses) during pregnancy does not jeopardize the newborn. Blood group typing and direct Coombs' test should be performed in every newborn of an Rh negative mother to establish whether there is a necessity to administer anti-D. In the presence of a positive direct Coombs' test, the type of antibodies should be identified.